An undefined function is a function that fails to execute when called due to the body of the function not being available to the program, compiler, or interpreter, looking for a function definition.
Questions tagged [undefined-function]
143 questions
107
votes
14 answers
Undefined function mysql_connect()
I have ran aptitude install php5-mysql (and restarted MySQL/Apache 2), but I am still getting this error:
Fatal error: Call to undefined function mysql_connect() in /home/validate.php on line 21
phpinfo() says the…

user1765369
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65
votes
8 answers
PHP fileinfo is undefined function
Whenever I try to get the mime content type from php, it echos:
Fatal error: Class 'finfo' not found in /home/jobynadel/finadel.com/video/finfo.php on line 4
or
Fatal error: Call to undefined function finfo_open in…

Jobynad
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30
votes
3 answers
Why does the C++ linker allow undefined functions?
This C++ code, perhaps surprisingly, prints out 1.
#include
std::string x();
int main() {
std::cout << "x: " << x << std::endl;
return 0;
}
x is a function prototype, which seems to be viewed as a function pointer, and C++…

chmullig
- 13,006
- 5
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28
votes
3 answers
Undefined method 'pluralize' for #
Not sure why this has decided to stop working.
customers_controller.rb
redirect_to customers_url,
notice: pluralize(@imported_customers.size, "customer") + " imported!"
And I'm getting the error:
NoMethodError: undefined method…

Wes Foster
- 8,770
- 5
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23
votes
1 answer
Call to undefined function password_hash()
I am running php version 5.4.16 on localhost right now, while I am developing my site. I want to use password_hash(), but I keep getting this error:
Fatal error: Call to undefined function password_hash() in /dir/to/file.php on line 123
Why is…

user3162085
- 241
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22
votes
4 answers
pcntl_fork() returning, Fatal error: Call to undefined function pcntl_fork()
I'm trying to fork a command line run XAMPP php process using pcntl_fork(). When I run the command below:
$pid = pcntl_fork();
if($pid == -1){
file_put_contents('testlog.log',"\r\nFork Test",FILE_APPEND);
return 1; //error
}
else if($pid){
…

Ben Pearce
- 6,884
- 18
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8
votes
1 answer
Laravel: Call to undefined function Symfony\Component\Console\mb_convert_variables()?
I'm running a vanilla Amazon EC2 server. I installed PHP 5.5.21 myself. My web application is built on Laravel. For weeks, everything was working flawlessly. Now, however, when running the Laravel command to update the database schema:
php…

clone45
- 8,952
- 6
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8
votes
1 answer
Are all unused undefined methods allowed?
Here’s a class with an undefined method. It seems compilers allow instances of this class to be constructed, so long as the undefined member function is never called:
struct A {
void foo();
};
int main() {
A a; // <-- Works in both…

CodeBricks
- 1,771
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5
votes
2 answers
How to make function useable only for a certain data constructor of an ADT?
I'm currently playing around with ADTs in Haskell and try to build an ADT Figure:
data Figure = Rect { x :: Integer, y :: Integer, width :: Integer, height :: Integer}
| Circle { x :: Integer, y :: Integer, radius :: Integer}
…

Markus Weninger
- 11,931
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4
votes
1 answer
touchableopacity onpress function undefined (is not a function) React Native
I want to be able to navigate to a new screen after tapping the TouchableOpacity button but I receive an error which says
_this3.handleThisTap is not a function. (In '_this3.handleThisTap()','_this3.handleThisTap' is undefined)
import React, {…

iprateekk
- 596
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3
votes
1 answer
PHP Fatal error: Call to undefined function Laravel tinker
I'm trying to establish a relation between two tables (Roles and Abilities) but when I run the function allowTo() it says is undefined.
I tried to clear the cache and config but didn't do anything.
If anyone could help that'd be great, thanks!
Model…

Becks
- 33
- 5
3
votes
3 answers
Angular 5 typeerror:
I am using Angular 5 in a project and i get a typescript error:
ERROR TypeError: Cannot read property 'indexOf' of undefined
What my code is supposed to do is to update the template on input change like this:
The template:

Gabriel
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3
votes
1 answer
Error Undefined function in Erlang
This on compiling gives {ok,assignment5}.
three_a(F) -> fun(Y) -> lists:foldl(F,0,Y).
After writing this
F1=assignment5:three_a(fun(X,Sum) -> X+Sum end).
Gives
** exception error: undefined function assignment5:three_a/1
Please help out!

Mishal Shah
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3
votes
2 answers
WordPress wp-cli generates error: "Call to undefined function getallheaders"
The wp-cli tool is a very handy way to execute WordPress tasks from the command line. However if the WordPress Site contains plugins or theme initialization code that calls the PHP getallheaders method then wp-cli will not work. It will instead…

jambroseclarke
- 261
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3
votes
2 answers
Cloud9 cURL not working
I was just fiddling with php on cloud9 the other day and I can upon this problem that cURL did not seem to be working. When you make a php workspace in cloud9, there is autocomplete for cURL so they must know about it. Here is the…

Holger Kibur
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